I would actually say the (indoor) mall apocalypse is a contributing factor since for all their faults, malls were third places in a way that strip shopping centers are not.
At least for retail the problem is moreso that lenders and landlords are playing hot potato with inflated rent and extend and pretend; some(most?all?) commercial loans go into default if rent goes below a certain amount
Not a super useful metric because third places probably wouldn’t be zoned residential. This is like saying 75% of fruits are apples, so there’s no room for asparagus
Ideally they would be in a place zoned residential, just not exclusively residential. If everything is zoned for only single family homes, there won't be a third place nearby. The density is low and it's not mixed use.